The present invention relates to a method of and to an apparatus for manipulating a running web or strip of paper, metallic or plastic foil or other elongated strip-shaped foldable material. More particularly, the invention relates to improvements in methods of and in apparatus for gathering and manipulating stacked zig-zag formations of sheets or panels which are made of paper and/or a metallic or plastic material.
It is known to stack successive sections or panels of a continuous running web in zig-zag formations wherein the neighboring panels overlie each other and are joined along fold lines which can be weakened, e.g., by rows of perforations, by pronounced scoring and/or in any other suitable way. It is necessary to separate successive accumulations or stacks of overlapping panels from the web, e.g., for introduction of separated stacks into boxes, cartons or other types of receptacles. Separation of successive fully grown stacks from the running web presents numerous problems, either because it necessitates an interruption of the zig-zag folding operation or because the breaking of the web is unpredictable and cannot always be carried out at a predetermined location (e.g., along a selected fold line) so that the rearmost panel of a fully grown stack and/or the foremost panel of the next-following (growing) stack is damaged or destroyed. Moreover, heretofore known mechanisms for separating successive fully grown stacks from the web which is being converted into a pile of superimposed or overlapping panels in zig-zag formation are complex, bulky and expensive.